1. Field of the Invention
The present invention relates to a Brownie film and a camera for loading the Brownie film.
2. Description of the Prior Art
It is well known that xe2x80x9cJIS K 7512xe2x80x9d and xe2x80x9cISO 732xe2x80x9d standardize Brownie films. There are two types of the Brownie films, 120 and 220 types, and each of the types has a filmstrip and a light-shielding paper. For the 120 type, a light-shielding paper, called backing paper, that is longer than a filmstrip is used to cover backside of the filmstrip. In the light-shielding paper, a portion protruding from the leading end of the filmstrip becomes a leader, whereas another portion protruding from the trailing end of the filmstrip becomes a trailer. After inserting the trailer to a slit in a spool, the Brownie film is wound about the spool while the light-shielding paper covers the filmstrip. In the 220 type, leader and trailers are spliced to leading and trailing ends of the filmstrip respectively. The leader and the trailer are made of the light-shielding paper. After the trailer is inserted to the slit in the spool, the Brownie film is wound about the spool.
In both 120 and 220 types, the leader is wound about outermost turn of the rolled film to shield the filmstrip from ambient light. When loaded into a camera, the leader of the Brownie film is inserted into a slit in a spool, hereinafter referred to as a take-up spool, in a film take-up chamber. By film winding operation, the Brownie film is wound about the take-up spool while the leader constitutes innermost turn of the rolled film. The trailer is rolled around to cover outermost turn of a roll of the exposed filmstrip after accomplishing photography. When the exposed Brownie film is taken out from the camera, the trailer protects the filmstrip from ambient light.
The filmstrip has approximately 60 mm width. Standard length of the 120 type filmstrip allows to take twelve picture frames of 6 cmxc3x976 cm, eight picture frames of 6 cmxc3x979 cm, and sixteen picture frames of 6 cmxc3x974.5 cm. Upon manufacture, the filmstrip is recorded printing patterns along two lateral sides in a side printing process. The side printing process is called pre-exposure process. The printing patterns recorded in the side printing process, hereinafter referred to as side printing patterns, comprise film information, product information, characters, and marks. The film information is a type and a photosensitivity of the film. The product information is a manufacturer name, product lot number and serial number. The characters and marks include frame numbers, arrows indicating winding direction, and the like.
In FIG. 7 showing an example of conventional Brownie film, the side printing patterns are recorded as latent images and are visualized through processing of the filmstrip. Inside of upper lateral side portion of the filmstrip 2, there are first and second side printing patterns 3a and 3b alternatively printed. The first side printing pattern 3a is a combination of a manufacturer name xe2x80x9cABCxe2x80x9d and a film type xe2x80x9cRDP IIxe2x80x9d, whereas the second side printing pattern 3b is a combination of the film type and an emulsion number xe2x80x9c123xe2x80x9d. Moreover, along a lower lateral side portion, side printing patterns 3c, combinations of the film type and a frame number in which an arrow mark and numerals are combined, are printed at a constant pitch. Note that picture frames 4, shown in phantom lines, are in the size of 6 cmxc3x974.5 cm.
Among cameras for the Brownie films, are generally known five types of cameras in which picture frame sizes of 6 cmxc3x976 cm, 6 cmxc3x977 cm, 6 cmxc3x978 cm, and 6 cmxc3x979 cm are producible. Each of these cameras is provided with an exposure aperture in the same size of each picture frame. There are also exposure aperture changeable cameras. To make it possible to use the both 120 and 220 types of the Brownie film, it is well known that each of the cameras is provided with a function to shift a film pressure plate toward the optical axis direction according to thickness of the light-shielding paper.
In the Brownie film, depending on its size, a position of the picture frame deviates from the printed frame number, so the frame number is used as an index representing order of photography. After processing, the filmstrip is cut into picture frames. However, an arranging pitch of the side printing patterns 3c including the frame number is designed to be less than 45 mm in order to have the frame number in the smallest picture frame size of 6 cmxc3x974.5 cm.
Comparing to the 135-size film and IX 240 film, the Brownie film has significantly larger picture frames such that it is possible to take clearer photographs, so it is widely used by commercial and advanced amateur photographers. They usually record photographic conditions such as a focal length of a taking lens, a shutter speed, and an f-stop in each frame. Brownie cameras incorporating a data imprinting device are available in the market so that it allows the photographers to record printing patterns representing these photographic conditions, hereinafter referred to as individual printing patterns, on the film.
In the Brownie camera, the individual printing pattern is optically recorded outside of the picture frame with the data imprinting device to keep space for picture frames as large as possible. In a conventional Brownie film, as shown in FIG. 7, side printing patterns are printed on upper and lower lateral sides of the filmstrip 2. Therefore, there occurs a problem in which the individual printing patterns recorded with the data imprinting device overlaps the side printing patterns, then both printing patterns become illegible. The length of the picture frame along a longitudinal side of the filmstrip is depends on the type of the Brownie camera, so it is impossible to determine arranging pitch of the side printing patterns on the basis of the size of the picture frame.
In view of the foregoing problem, an object of the present invention is to provide a Brownie film and a camera in which side printing patterns are assuredly prevented from being overlapped by individual printing patterns.
Another object of the present invention is to provide a Brownie film and a camera in which two kinds of printing patterns are readable without error.
To achieve the above and other objects, side printing patterns are recorded only inside of a first lateral side portion that comes to upper side of the filmstrip that is perpendicularly pulled leftward from a spool, viewed from a base side. In a Brownie camera according to the present invention, individual printing patterns are recorded inside of a second lateral side portion by a data exposure head. To keep picture frame of sufficient size, side printing patterns are recorded within an area 2.5 mm, more preferably 2 mm, inside from the first lateral side.
A positional information indicating a position in a longitudinal direction of the filmstrip, for example, a frame number is disposed with its pitch not less than 25 mm and not more than 45 mm. Because the pitch is not more than 45 mm, at least one positional information completely remains in each cut frame, even if the filmstrip is cut into the smallest picture frame size of 6 cmxc3x974.5 cm. Moreover, if it is not less than 25 mm, it is possible to record printing patterns including much information in a sufficient space. It is more preferable to make said arranging pitch not less than 35 mm and not more than 43 mm in view of increase in information amount and keeping sufficient spaces for margins to avoid cutting in the printing patterns.
The side printing patterns and the individual printing patterns are recorded on different lateral side portions, so they do not overlap each other. Moreover, when posture of the filmstrip is determined such that images in picture frames that are visible through processing are shown as erect right images, side and individual printing patterns respectively become erect and right images. It may be possible to record the side printing patterns in the second lateral side portion, and to record the individual printing patterns inside of the first lateral side portion.
According to the present invention, the side printing patterns and the individual printing patterns are respectively recorded in different lateral side portions, so both printing patterns do not overlap. Moreover, the side printing patterns are printed in erect right images in the first lateral side portion that comes to the upper side of the filmstrip pulled leftward from the spool, viewed from the base surface side opposite of the emulsion layers, so as to be in the same posture as photographic images in the picture frames. Therefore, it is easy to observe the photographic images and the side printing patterns. Moreover, the side printing patterns are recorded within a region where is 2.5 mm inside from the lateral side portion, so it is possible to keep sufficient space for the picture frame.
Furthermore, the side printing patterns include the positional information pattern indicating positions in a longitudinal direction of the filmstrip, and its arranging pitch is not less than 25 mm and not more than 45 mm. Even when the filmstrip is cut into frames of the smallest size after processing, each frame has at least one positional information pattern. Thus, it is possible to avoid an inconvenience in which the photographic order becomes indefinite.